Field of the Invention
This invention relates to a small boat collision avoidance apparatus.
Description of Related Art
With motorboats and other small craft, when a number of boats are navigating on the sea at a distance from one another, such as when a group of owners of boats equipped with same-type radio-wave transceiver units go night fishing together, collisions sometimes occur because boats of the group are apt to come close to each other without noticing owing to poor visibility at night. The risk of collision increases when the weather worsens and rain or fog sets in.
A technical concept put forth in Japanese Unexamined Patent Publication No. H08-189,966 with this in mind proposes that one boat or similar randomly transmits same-strength radio-wave signals, and another navigating boat receiving the radio-wave signals discriminates distance to the one boat from the strength of the signals and produces a warning when the discriminated distance is within a predetermined distance.
As set out above, the technology of the reference is configured to avoid collision with another boat coming within the predetermined distance, but it does not detect position of the other boat and therefore cannot ensure collision avoidance definitely.